This invention relates in general to infrared imaging and, more particularly, to infrared imaging in a passageway.
Thermal imaging has developed rapidly over the past several years. Obtaining information based on temperature differences has proven to be an effective and accurate way to gather information in certain applications. Thermal imaging systems generally include a collecting component, an infrared detector, a circuit, and a display. The collecting component images infrared radiation onto the infrared detector. The infrared detector then generates electrical information that is sent to the circuit. The circuit converts the electrical information into electrical data which is displayed on the display. Thus, the display shows a visible image which represents the infrared radiation collected by the collecting component. These thermal imaging systems have been generally adequate for their intended purposes, but have not been satisfactory in all respects.
A problem with current thermal imaging systems is that they are too large to be used to gather information within the interior of small passageways. In the area of medicine, such passageways include a blood vein or artery. For example, in diagnosing potential heart problems, early detection of weaknesses or blockages of blood veins or arteries is critical. One cause of heart attacks is the presence of lesions within blood veins. The lesions can become inflamed and erupt, introducing debris into the veins which can trigger a heart attack, even when the blockage within veins and arteries is low. When inflamed, the lesions have a higher temperature than surrounding portions of the interior surface of the blood veins, and could thus theoretically be detected by infrared imaging techniques. However, as noted above, existing infrared imaging equipment is too large to be used within a passageway as small as a blood vein.
There are also industrial applications in which thermal imaging within a very small space is of interest, for example for inspection of certain types of equipment. Again, existing infrared imaging systems are too big to be inserted into such small spaces.
A further consideration is that prior systems used an infrared detector that had to be cooled, and the presence of a cooling mechanism makes the overall system relatively expensive.
From the foregoing, it may be appreciated that a need has arisen for a method and apparatus for infrared imaging in places such as a small passageway. According to the present invention, a method and apparatus are provided to address this need, and involve: transmitting infrared image information through an elongate optical portion from a first end thereof to a second end thereof; collecting infrared image information and supplying it to the first end of the optical portion; and receiving infrared information at a section which includes an infrared image detector and which directs infrared image information from the second end of the optical portion onto the image detector.